It’s not known how seriously Kemp will consider Markwalter, who has never sought political office before. But he’s been frequently mentioned in Republican circles as a potential candidate.
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About 500 candidates have applied online to succeed Isakson, who is retiring because of health concerns. Whoever Kemp picks would stand for election in November 2020 to fill out the remaining two years of Isakson's term – and be expected to run again in 2022.
Among the biggest names seeking the appointment are U.S. Rep. Doug Collins, ex-U.S. Rep. Jack Kingston, former Health Secretary Tom Price, and House Speaker Pro Tem Jan Jones, the No. 2 Republican in the state House.
Some other well-known figures are aiming for the seat, too, including current and former state lawmakers, a U.S. ambassador, decorated military veterans, radio commentators and former Kemp aides.
The majority of the applicants won't be seriously considered, although some make strong cases that they should be. They hope Kemp goes with a non-conventional appointment, such as a judge or business executive with little or no political experience.
Meanwhile, a number of potential appointees who could make strong cases to Kemp have stayed on the sidelines for varying reasons, a list that includes Attorney General Chris Carr, Lt. Gov. Geoff Duncan, U.S. Rep. Tom Graves, and state Agriculture Commissioner Gary Black.
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The Democratic side of the contest has gotten off to a quiet start. Matt Lieberman, an entrepreneur and son of former Sen. Joe Lieberman, told The Atlanta Journal-Constitution earlier this month he was entering the contest so he could be a voice for "fed up" Georgians.
But he won't have the support from national party leadership, and a half-dozen or so Democrats are kicking the tires on the race now that a few of the bigger names – Stacey Abrams and U.S. Rep. Lucy McBath among them – have passed on a run.
Four other Democrats are running in Georgia’s other Senate race against Perdue, a former Fortune 500 chief executive who won an 8-point victory in 2014 and is seeking a second and, according to him, final term.
They are: Business executive Sarah Riggs Amico, who lost a 2018 run for lieutenant governor; journalism executive Jon Ossoff, who lost a 2017 bid for Congress; Clarkston Mayor Ted Terry and ex-Columbus Mayor Teresa Tomlinson.